Data/hora: 26/09/2024 07:26:31

Biblioteca(s): 	Embrapa Café.	
Data corrente: 	11/12/2017	
Data da última atualização: 	11/12/2017	
Autoria: 	COELHO, S. V. B.; ROSA, S. D. V. F. da; CLEMENTE, A. da C. S.; PEREIRA, C. C.; FIGUEIREDO, M. A. de; REIS, L. V.	
Afiliação: 	STEFANIA VILAS BOAS COELHO, UFLA; STTELA DELLYZETE VEIGA F DA ROSA, SAPC; ALINE DA CONSOLAÇÃO SAMPAIO CLEMENTE, UFLA; CRISTIANE CARVALHO PEREIRA, UFLA; MADELEINE ALVES DE FIGUEIREDO, UFLA; LEANDRO VILELA REIS, UFLA.	
Título: 	Tolerance of Coffea arabica L. seeds to sub zero temperatures.	
Ano de publicação: 	2017	
Fonte/Imprenta: 	Ciência e Agrotecnologia, v. 41, n. 3, p. 312-321, May/Jun. 2017.	
Idioma: 	Inglês	
Notas: 	Título em português:  Tolerância de sementes de Coffea arabica L. à temperaturas sub zero.	
Conteúdo: 	Preservation of the quality of coffee seeds is hindered by their intermediate behavior in storage. However, long-term storage at sub zero temperatures may be achieved by adjusting the water content of the seeds. The aim of this study was to evaluate the tolerance of coffee seeds to freezing, in relation to physiological and enzymatic modifications. Coffee seeds were dried in two manners, rapid and slow, to water contents of interest, 0.67, 0.43, 0.25, 0.18, 0.11, and 0.05 g H2O g-¹ dw (dry basis). After drying, the seeds were stored at a temperature of -20 ºC and of 86 ºC for 24 hours and for 12 months, and then compared to seeds in cold storage at 10 ºC. The seeds were evaluated through calculation of percentage of normal seedlings, percentage of seedlings with expanded cotyledonary leaves, dry matter of roots and of hypocotyls, and viability of embryos in the tetrazolium test. Expression of the enzymes superoxide dismutase, catalase, and peroxidase were evaluated by means of electrophoretic analysis. Only seeds dried more slowly to 0.18 g H2O g-1 dw present relative tolerance to storing at -20 °C for 12 months. Coffee seeds do not tolerate storage at a temperature of -86 ºC for 12 months. Water contents below 0.11g H2O g-¹ dw and above 0.43 g H2O g-¹ dw hurt the physiological quality of coffee seeds, regardless of the type of drying, temperature, and storage period. Coffee seed embryos are more tolerant to desiccation and to freezing compared to whole seeds, especially when the seeds are dried to 0.05 g H2O g-¹ dw. The catalase enzyme can be used as a biochemical marker to study tolerance to freezing in coffee seeds.	
Palavras-Chave: 	Antioxidant enzymes; Enzima antioxidante; Saturated saline solutions; Solução salina saturada.	
Thesagro: 	Congelamento; Secagem.	
Thesaurus Nal: 	Drying; Freezing; Silica gel.	
Categoria do assunto: 	--	
URL: 	http://ainfo.cnptia.embrapa.br/digital/bitstream/item/168585/1/Tolerance-of-Coffea-arabica-L.-seeds.pdf	
Registro original: 	Embrapa Café (CNPCa)	
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